Patent GB-191416371-A (GB)
Title: Rotary Hook Sewing Machine.
Inventor: FAIRWEATHER WALLACE
IPC: D05B73/12
Filed: 1914-07-09
Granted: 1915-07-08
Abstract: 16,371. Fairweather, W., [Singer Manufacturing Co.]. July 9. Sewing-machines; lock-stitching by hooks; governing under or shuttle thread.-A trtary loop-taking device for use in lock-stitch sewing- machines, particularly those in which the looptaker actuating-shaft is transverse to the needle path, comprises (1) a rotary loop-seizing member 17, Fig. 10, having a beak 24, (2) a thread case 27, Fig. 9, fitting in a suitable bearing within the member 17, and carrying at its forward end a loop guard 46, Fig. 15, provided with a spring device to tension the underthread; and, (3) a loop-distending beak 34, Fig. 11, which is restrained from rotation. The member 17 is mounted upon a disk 15 on the actuating-shaft 14, to which is imparted two revolutions for each reciprocation of the needle. An annular channel 19 is formed between two walls 17, 18. The beak 24 and a loop-discharging point 25 are formed by cutting slots 22. 23 in the walls. A loop-stop 26 is placed across the slot 22. The thread case 27 is provided with a flange 28 which is journaled against the ledge 20 on the member 17. A groove 29, Fig. 3, in this flange filled with packing-material saturated with oil provides the necessary lubrication. A series of inclined slots in the flange, which become filled with lint &c. serves to distribute the lubricant effectively. The loop - distending beak 34, together with a shorter beak 35 are mounted on a plate 33, secured by a screw to the base of the thread case. The beaks 34, 35 operate in the channel 19. The thread spool is mounted upon the post 36 and is secured by a lever 85 with a cam portion 84, which controls a spring- operated plug 78 and ejecting - lug 81. The flange 28 is provided with an extension 40 upon which is secured a segmental guard 45 having a flange 46, and a loop-discharging finger 47, into which the adjacent edge of the flange 46 merges. The guard is spaced apart from the extension 40 by a boss 45<1>, Fig. 21. The finger 47 enters a cavity extending laterally from the needle hole in the throat plate, and a finger depends from the throat plate 50 in the direction of the feed to co-operate with the finger 47 in receiving the needle-thread loop preparatory to its final discharge into the fabric. The thread case is held from rotation by a pair of fingers 68 on a rocking yoke 69, which fingers are adapted to engage holes 67 in the flange 28, The bobbin thread is led out through the slot 38 and along the taper passage between the reduced wall of the thread-case extension 40 and the guard 45. It then passes into the slots in the rounded ends of two studs 63, 64, which enter corresponding pockets in the extension 40. Between the two studs, the thread is acted upon by a stud or extension at the end of a regulatable spring 58. The thread is finally led over the face of the finger 47 to the needle-hole in the throat plate. The loop formed by the needle is seized by the beak 24 and passes down the slot to the loop-stop 26. The inner limb of the loop is engaged and distended by the stationary beak 34. The outer limb of the loop is forced over the edge of the member 17 by the bevelled flange 17<1>. The loop is then carried over the thread case to the position at which the take-up begins its operative movement. The thread is drawn off over the guard 45 to prevent excess of slack, and the inner limb is secured between the beak 35 and the point 25 until the hook has completed substantially the first rotation. The flange 46 acts to bridge over the gap between the beak 24 and the point 25. The thread loop is drawn off the point 25 around the finger 47, upon which it is yieldingly detained by the finger depending from the throat plate.